This invention relates to a device for securing a cable, especially surgical cables.
Surgical procedures for the repair or fusion of large and small bones, ligaments and tendons, and other orthopedic procedures frequently require use of an orthotic device or attachment apparatus which can be subject to tensioning and bear heavy loads caused by the unique anatomical features of the compromised bone or tendon. For example, fractures of the patella are exposed to high stresses during flexion and extension of the knee joint; fusions of the spinal vertebrae are exposed to high gravitational forces and movements of the spinal column; torn ligaments and tendons are exposed to high stresses due to contraction of the associated muscle or flexion and extension of the bony structures; and trochanteric reattachment and cerclage techniques involve cable that is tensioned and exposed to high weight loads and stress factors.
Examples of surgical cable attachments include U.S. Pat. No. 4,966,600 to Songer et al. Clamps for holding the cables are shown in U.S. Pat. No. 6,053,921 to Wagner et al. A polyethylene cable system is described in U.S. Pat. No. 5,456,722 to McLeod et al. Polyethylene cable tying is shown in U.S. Pat. No. 5,628,756 to Barker Jr., et al.
U.S. Pat. No. 6,214,007 to Anderson shows a fastener where soft tissue grafts are fixed in place by a screw whose threads are affixed to bone and whose head together with a collar trap the graft therebetween. The screw is threaded into bone.
The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is xe2x80x9cprior artxe2x80x9d with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. xc2xa71.56(a) exists.
The invention provides a clip designed to grip and hold a tension band or cable without the use of any additional securing features such as knots. It is especially well suited for use with braided polyethylene cable. It employs a tapered screw concept which is customized using radii at both the root and crest of the thread. This prevents cutting of the cable. Standard clip designs using sharp teeth would cut individual cable strands leading to cable failure.
The cable design allows for easy engagement (starting of the thread) with progressively more compression of the braided cable. The female thread of the outer body is designed with a large radius where the cable exits to form a loop. All exiting edges are radiused. The thread profile follows the main taper and thus blends gradually to zero depth. This, along with the large exit radius, minimizes all sharp bends which act to cut the cable under cyclic loading.